BB Wildlife 59BEES
July 2020
oil-producing glands
on their petals. In
South Africa, co-evolution
with twinspur flowers has led
to oil-collectors with front legs twice
the length of their bodies – awkward for
walking, but perfectly suited to scraping
their favourite meal from the deep tubes of
their preferred blossoms.Home sweet home
Varied nesting opportunities have also
helped spur the diversity of bees. Since
mating often occurs precisely when and
where they emerge from their winter sleep,
exploiting different nest sites can quickly
lead to the kind of reproductive isolation
necessary for making new species.
Like mining bees, many sweat bees and
masked bees dig tunnels for their nests,
adapting to conditions that range from cliff
faces to sand dunes to hard-packed earth.TheNatural
History
Museum’s
GavinBroadanswers
someburningquestions.Q
Why are bees and
other pollinators
so important?A
It’s estimated that the value of
pollination for human food is
in excess of £110 billion per year, so
the collapse in numbers of bees has
provoked alarm. The focus is usually
on the honeybee, with the spread
of the Varroa mite, pesticides and
colony collapse disorder, however
this is just one pollinator among
many. Occasionally bumblebees,
solitary bees and butterflies get a
look in, but other pollinators, such
as flies, beetles and moths, are
often overlooked.Q
Why are bees and other
pollinators in decline?A
There is good evidence that
neonicotinoids (pesticides)
have adverse effects on pollinators.
It’s also pretty destructive to mow
large amounts of flower-rich habitat
when insects are just getting going,
and before those flowers have set
seed. We should all support ‘No
Mow May’!
Some pollinators are in decline,
especially specialists, bees and
other insects that rely on particular
habitats. However, it’s also the case
that some generalists are doing well- bumblebees offer some nice
examples.Somespecialistssuch
asBombuscullumanusandB.
subterraneus, whichrequireflower-
richmeadowsandwereontheedges
oftheirrangesinBritain,havegone
extinct.Otherscanthriveinmore
alteredlandscapessuchasBombus
terrestris, andinthecaseofBombus
hypnorum, havearrivedrecentlyand
rapidlyspread.Q
Howcanpeoplehelp
pollinatorsathome?A
I wouldsuggestthatgardens
willbenefitfroma goodvariety
ofnativefloweringplants.Pollinators
willoftenlovevariousnon-native
flowers,whichsupplyplentyof
nectarandpollen,butthesespecies
offerlittletotheotherinsects
thatwouldbeeatingfoliageand
seeds.Letyourlawngrowa bit.I
knowpeoplewhoareveryhappy
thattheirlawnshavetransitioned
froma bowlinggreentoa space
wheregrassesareintheminority.Q
Arenon-pollinating
insectsimportant,too?A
Yes,it’snotjustaboutthe
pollinators.Allinsectsplay
importantrolesinourterrestrial
andfreshwaterecosystems,as
herbivores,predators,decomposers
andfoodforotherorganisms.If
populationsoflargenumbersof
insectspeciesaredeclining,
whatdoesthatsayaboutour
stewardshipofthelandscape?Left: mow later in
the year to help
pollinators. Right:
Varroa mites.The beauty of this bee
is deceiving, as it is a
parasitic species whose
larvae eat the collected
pollen meant for the blue-
banded bee larvae (which
then starves to death).NEON CUCKOO BEE
THYREUS NITIDULUSLeft to right: Andy Sands/NPL; Oliver Wright; Erica Siegel Wildlife Photography; Elena Litsova/Getty; GettyContinues on next page...